An Active Matrix/Organic Light Emitting Diode (AMOLED) television and an AMOLED display module both have a problem of non-uniform displaying, that is, both have a phenomenon of Mura of various traces caused by non-uniformity of brightness of the display. By means of optical measurement, relatively poor uniformity of the brightness of the display can be observed.
An AMOLED is a current type light emitting device, thereby being greatly affected by a current. It is very hard to make the uniformity of a back plate satisfactory due to the limitation of the current process, so that the non-uniformity of the current is caused. The non-uniformity of the current can cause the non-uniformity of the brightness, thereby resulting in the non-uniform displaying of an AMOLED display.
In addition, an Electro Luminescent (EL) process comprise an evaporation deposition type, an ink-jet printing type and the like, and can cause the non-uniformity of electrical characteristics of an OLED, and such non-uniformity will also cause the non-uniformity of screen displaying.
To improve the uniformity of the AMOLED display panel, some compensating technologies can be generally employed to reduce the brightness difference of a screen. An external compensating technology in the compensating technologies is equivalent to a feedback mechanism. FIG. 1 is a schematic diagram of a compensating feedback mechanism in an AMOLED compensating technology. In such compensating technology, the non-uniformity degree of the display panel is detected firstly to form data, and this data is equivalent to a historical file of the corresponding display panel, and reflects a physical attribute of this display panel. Then, the data is transmitted to an image data processing unit, and the image data is corrected by the image data processing unit. The gray scale of image data on an original slightly-bright position of the display panel is reduced to form new image data, and then the new image data is transmitted; the gray scale of image data on an original slightly-dark position of the display panel is increased to form new image data, and the new image data is transmitted. Such processing thought is similar to a negative feedback design in a circuit, that is, the information of an output terminal is reversely transmitted to an input terminal, so that the information of the input terminal is corrected, and finally a dynamic equilibrium is achieved.
An optical compensating technology is one of external compensating technologies. An AMOLED optical compensating apparatus uses an optical CCD device to shoot an illuminated AMOLED display panel to obtain brightness data of each pixel. Then, this apparatus processes and analyzes the obtained brightness data to form burnable data which can be called by a chip. Then, this apparatus burns the data onto a flash chip. It is required to be changed into another set of programs when booting up again; as illustrated in FIG. 2, this program can read the data stored by the flash chip, and stores the data in a Synchronous Dynamic Random Access Memory (SDRAM). When the screen normally works, the data in the SDRAM is read at any time for processing input image data so as to form compensated data, and the compensated data is transmitted to the AMOLED display panel.